Facts:The purpose of OPEC for members is to "coordinate and unify the petroleum policies of its Member Countries and ensure the stabilization of oil markets in order to secure an efficient, economic and regular supply of petroleum to consumers, a steady income to producers and a fair return on capital for those investing in the petroleum industry."

Timeline:September 14, 1960 - OPEC is formed in Baghdad, Iraq, by founding members Iraq, Kuwait, Iran, Saudi Arabia and Venezuela.

November 6, 1962 - OPEC is registered with the United Nations Secretariat (UN Resolution No. 6363).

1973-1974 - Due to United States support of Israel in the Arab-Israeli conflict, the members of OPEC decide to raise the cost of oil from $3/barrel to around $12/barrel.

October 1973 - OPEC issues an embargo against the United States, halting oil exports. Customers in the United States experience long lines at gas stations and at times cannot find gas at all. Prices go from 36 cents a gallon in 1972 to over 50 cents a gallon in 1973.

March 18, 1974 - At an OPEC meeting, seven members lift the ban on exports to the United States: Algeria, Saudi Arabia, Kuwait, Qatar, Bahrain, Egypt and Abu Dhabi. Libya and Syria refuse to drop the ban, and Iraq boycotts the talks.

December 31, 1974 - Libya lifts its 14-month-old oil embargo against the United States.

November 2007 - Ecuador rejoins OPEC after a 15-year absence.

May 2008 - Indonesia announces that it will leave OPEC in 2009. The country is currently a net importer of oil, due to falling production from aging wells.